I'm getting an exception "Import-SPWeb: A duplicate field name 'guid' was found."

How can I track this down what field this might be? If it's a field in the target that has the same GUID in the source, shouldn't the force parameter on Import-SPWeb overwrite it on the target? Ultimately, what do I do about it?

EDIT

@Gilloux - thanks for the pointer. Now for some more info.

The site I'm exporting / importing I think was derived from a MOSS 2007 Collaboration Site template. I think... When I created the target site as a Blank Site, I received an error stating that the target needed to be created from the template SPS#0.

The ULS has an entry:

"Failed to find generic XML file at '[14 hive]\Template\SiteTemplates\SPS\xml\vwstyles.xml", falling back to global site definition."

The folder is present, but this file is not.

From what I've been able to find out, SPS#0 is an obsolete template so this may be at least part of the problem.